Young Researchers at Vanguard of Science in Japan
Awardees Speak about Their Work and Aspirations

Evolution of Human Intelligence

Dr. Nobuyuki Kawai 2004-present: Associate Professor, Graduate School of Information Science, Nagoya University 2001: Assistant Professor, Graduate School of Human Informatics, Nagoya University 1999: COE Postdoctoral Research Fellow, Primate Research Institute, Kyoto University 1998: Received Ph.D. from Kwansei Gakuin University 1996: JSPS Postdoctoral Research Fellow, Kwansei Gakuin University 1995: Kwansei Gakuin University (completed doctoral course) 1994: JSPS Doctoral Course Fellow, Kwansei Gakuin University 1990: Graduated from Kwansei Gakuin University

My main interest has been to address why humans are so intelligent. I have been conducting learning, memory and attention studies on humans and non-humans to discover the key to human-specific intelligence. I am also interested in finding which aspects of human cognition are shared with other non-human animals, especially primates. In order to determine the boundaries of human cognition, I have conducted psychological experiments from developmental and evolutionary perspectives.

We investigated the behaviors of crayfish (an invertebrate animal) to clarify a simple form of learning. We found that crayfish can learn to avoid an electric shock, though their behavior was not as flexibly changeable as vertebrate animals. We have also explored the origins of learning and memory from developmental perspectives. We found that a chimpanzee fetus can form an association between an extrauterine tone and vibroacoustic stimulation using a classical conditioning procedure.

We also focused on the higher cognitive processes of non-human animals. Employing the language- and numerical-trained chimpanzee-Ai, we tested her short-term memory span, which is essential for humans to engage higher cognitive processes such as mental calculation and conversation. We found that Ai had a memory span comparable to that of human adults. This research was published in Nature. Fortunately, some of my research has also been introduced in newspapers and TV programs both in Japan and other countries.

Humans are highly intelligent in not only physical but also social domains. Humans can discern others’ intentions by subtle cues such as gaze directions or voice inflections. Humans can even tell the subtler difference between a real and fake smile. I plan to study how such affective information is communicated, and to clarify this mechanism as well as to elucidate the psychological and physiological changes that occur in the communication of various affective messages. In doing this, I will measure brain functions (e.g., by electroencephalogram) and physiological reactions like heart rate in combination with psychological experiments. I hope to eventually reveal how and why humans have evolved to become what we are today.